Vietnamese experience the highest incidence and mortality rates of liver cancer (hepatocellular carcinoma -- HCC) than any racial and ethnic groups in the U.S. Hepatitis B virus (HBV or hepB) is a strong risk predictor of HCC and the risk of liver cancer among the chronically infected is 200 times greater than for those not infected and 1 in 4 persons with chronic infection dies of cirrhosis or HCC. Screening and vaccination, in addition to being the most effective means of preventing HBV infection, can reduce HCC incidence and mortality rates. With an incidence rate of 11 times higher than that of White males (41.8/100,000 vs. 3.7/100,000),Vietnamese males face the greatest disparity in HCC, suffer and die disproportionately from undetected, untreated and unmanaged infection-related liver cancer. Our studies in PA and NJ revealed low rates of HBV screening and vaccination (7.5% and 6.3% respectively), identified multiple and complex barriers to screening and vaccination, and a serious lack of programs tailored to the needs and barriers of this medically underserved community. There is a paucity of research on testing the effectiveness of HBV screening and vaccination intervention in Vietnamese adults. Our CBPR-based pilot study has demonstrated acceptability and feasibility of conducting the proposed multifaceted and innovatively-tailored HBV intervention in Vietnamese communities. The proposed randomized trial will test the effectiveness of a community-based liver cancer intervention in increasing hepB screening as well as vaccination for high-risk never screened Vietnamese. In addition, the study will evaluate the effectiveness of increasing knowledge about hepB, perceived risks, susceptibility to and benefits of screening and vaccination, as well as reduced barriers to screening and vaccination. The study is a 2-arm group randomized trial with 42 community organizations (40 participants per site, a total N=1680). An integrative framework of Health Belief Model and Social Cognitive Theory will be applied to the study to address both individual factors and healthcare system barriers. The proposed study is expected to yield important and new data on the intervention effects. If this community-based hepB intervention trial proves effective, it can be used as a model program that has potential transportability to and sustainability in Vietnamese and other Asian communities nationally, hence make a substantial contribution toward reducing cancer health disparities.